Survey: 34% of teens in poor fitness

CHICAGO (AP) -- About a third of U.S. teens would flunk a treadmill fitness test, a new study shows, meaning that more than 7 million youngsters could face higher risks for heart disease later in life.
While that finding is not surprising -- given previous research showing that about 16 percent of U.S. schoolchildren are seriously overweight -- it's "very concerning," said Dr. David Ludwig, director of the obesity program at Children's Hospital Boston.
Dr. Ludwig, who was not involved in the study, called treadmill tests a good measure of fitness. He said the results show that "at a time in life when adolescents and young adults should be at peak levels of fitness, there's in fact a very high prevalence ... of very low fitness."
National analysis
The analysis of nationally representative data from government health surveys by Northwestern University researchers found that 34 percent of girls and boys aged 12 to 19 showed a poor level of cardiovascular fitness on an 8-minute treadmill test.
The tests became faster and steeper after a 2-minute warm-up, and a rapidly increasing heart rate after just a short period of exercising defined poor fitness.
The study included 2,205 adolescents and 3,110 adults aged 20 to 49 who participated in the 1999-2002 surveys.
About 14 percent of the adults showed a poor level of fitness, but that underestimates the true number who are unfit because adults with high blood pressure and other cardiovascular risk factors were excluded from the treadmill test, said lead author Mercedes Carnethon.
Teens and adults with poor fitness were two to four times more likely to be overweight or obese than those considered moderately or highly fit, the study found. Waist size, cholesterol levels and blood pressure also were higher in those in the low fitness category.
The study appears in Wednesday's Journal of the American Medical Association.
Copyright 2005 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.